Bob,
Welcome to the site. No doctors here, just people caring for or with bladder cancer, so no medical advice. This is a great place to get a patient's perspective on issues, either by asking or from reading the files.
Seems that you have a cancer care team already, and you may have good reason to accept their judgment.
There may be a variety of opinions heard here - you have to decide what is best for you.
Caught early, bladder cancer can be quite treatable. Sometimes a TURBT and regular observation, watching for the highly likely return, is the course for BC.
I would (and did) be asking for some further investigation, both at the start and regularly. I confess to feeling uncomfortable trusting a pair of eyes looking into my bladder to be the only diagnostic tool deciding what the cancer is doing. That's just me.
Bladder cancer can move up and down the urinary tract. Additional tests might be a waste of time and money OR they might catch a problem early. I'd like to catch anything early.
Below is a link to the American Cancer Society (ACS) file on BC diagnostic tools. This file has good background information.
www.cancer.org/cancer/bladdercancer/detailedguide/bladder-cancer-diagnosis
I have been through the full set of tests, except the bone scan, but my situation is most likely different from yours. I presented with symptoms, and there was confusion as to the cause at first. Finally, a complete workup, as described in the file, provided good information.
People here report a variety of treatment plans for similarly described situations. Clearly there is a lot of variation between care teams. You may or may not want to consider getting a second opinion from a major cancer center, given your history - you call.
Again, this is not medical advice, but a description of other possibilities. Talk to your doctors about any of your concerns, and be prepared with good information.
Best,
Jack